SHEBOYGAN – In these parts, where cows, horses and pigs mosey about rolling farmland and tractors haul bales of hay on tiny county roads, the only high-speed chase can be found at the top of the leaderboard of the 97th edition of the PGA Championship.

With jagged and dangerous Whistling Straits vulnerable Saturday from overnight rains, little wind to speak of and balls flying like never before this week because of 90-degree temperatures, players took aim, attacked and raced forward in the third round of the last major of the season.

No one came home faster than American boy wonder Jordan Spieth and the Thunder from Down Under, Jason Day. Seeking his first major victory, Day made five birdies and an eagle in his final 10 holes to shoot 6-under-par 66 and move to 15 under par for a two-shot lead.

Spieth, who won the first two majors of the season and with a victory on Sunday could overtake Rory McIlroy as the No. 1 player in the world, fell five shots back of the leaders but finished birdie-birdie-birdie and made six birdies in all on his inward nine to shoot 65. For the fourth time this year, he’ll play in the final group on the final day of a major.

“I was impatient on the front nine,” Spieth said. “I felt like I was playing some solid golf and I was 1 under through 10. I just wasn't scoring. My score did not reflect the way that I was playing, which has been a little bit of the story this week, minus two stretches of nine holes.

Jordan Spieth hits his tee shot on the 9th hole during the third round of the PGA Championship at Whistling Straits.(Photo11: Brian Spurlock/USA TODAY Sports)

“And so once the one on 11 went (in for birdie), even though it was a simple up-and-down, I at least saw another birdie go. The one on 12 was nice. And we're off to the races. The holes started to look bigger. … And on the back nine it was nice to get in the zone. So yeah, very, very pleased to have a chance to win another major.”

Saturday is traditionally moving day, but this Saturday was at warp speed. When fellow Aussies Day and Matt Jones signed their scorecards to end the day, there were eight players within six shots of the lead. Expect more of the same in Sunday’s final round, as temperatures will top 90 and winds aren’t expected to reach 10 miles per hour.

By the looks of things, and with perilous edges around every Whistling Straits dogleg, no one will break away from the pack.

And it’s an eclectic pack, too, as the leaders form a United Nations snapshot of the game’s global expansion. Players in the hunt hail from Australia, the U.S., South Africa, Germany, England and India. And then there is Tony Finau, the Utah native who is the only player on the PGA Tour of Tongan and American Samoan descent.

In third place at 12 under are South African Brendan Grace, who shot the low round of the day (64), and England’s Justin Rose (68).

Germany’s Martin Kaymer is at 11 under after a 65. Finau (69) and Jones (73) are at 10 under. American Dustin Johnson (68) and India’s Anirban Lahiri (70) are at 9 under.

“I've been here before, so I kind of know what to expect,” said Day, who has nine top-10s in 20 starts in majors but hasn’t broken his major. He fell two inches shy of joining a playoff in the British Open with a birdie putt on the 72nd hole, but then finished birdie-birdie-birdie the following week to win the RBC Canadian Open, gaining a huge amount of confidence.

“My confidence level is high, but I'm just more enjoying just being out on the golf course, rather than in previous positions that I've had in major championships, I've viewed them as very stressful and kind of hard to go out and play the next day,” Day said. “It's been fun to be out here in pressure situations. It's good to be in contention, especially on Sunday. It's good to have the lead, so that's a plus.”

Grace, who was tied for the lead on the 70th hole in the U.S. Open before driving his ball out of bounds, said he’s “finally getting the hang of America.”

“This is a dream to play out here,” Grace said. “I think I've been playing some great golf. The U.S. Open was a good one coming into this and even the Open Championship, just getting the confidence up, knowing that I can do it, can play in this environment and under this pressure.”

Grace played with Kaymer, who won this championship here in 2010 and is trying to join Tiger Woods as the only players to win the PGA on the same venue twice. As a reminder, Kaymer started the final round in the 2010 PGA Championship six shots behind and walked away with the Wanamaker Trophy.

“It's one of those things in major championships, the last round so much can happen,” Kaymer said. “I'm just glad that I put myself in a position to maybe have a chance tomorrow. It's such an interesting golf course. If you don't hit the ball well, you can shoot easily 75, 76. But if you hit fairways and make a couple of putts here or there, you can shoot a good score.

“And the greens are perfect. So if you place yourself on the fairway, you can be very aggressive with your iron shots. And if you're a good putter, you know, it's not up to the green, it's all up to yourself.”

Spieth once again is in position to win another major despite his youthful 22 years. After winning the Masters and U.S. Open, his bid for an unprecedented Grand Slam fell one shot shy of a playoff in the British Open.

But Spieth, who is going for win No. 5 this year, is trying to join Ben Hogan and Tiger Woods as the only players to win three majors in a season in the modern era. Further, Spieth would win the American Slam with a victory on Sunday, becoming the only player to win all three majors contested in the U.S. in the same year.

“Just to try to get my name on the Wanamaker Trophy, that's about it. That's the only history I'll be thinking of when we step on the first tee,” Spieth said. “ … I'll go into tomorrow strictly for the history piece of trying to get my name on a different major. It's a goal of mine to capture all four throughout my career. I've got a great opportunity to get the third right now.”